Treatment of oils and fats for the neutralization and removal of their fatty acid content



zATIoN AND v CONTENT Nov. 8, 192.7,"

TREATMENT 0F oILs -J. W. SPENSLEY AND FATS PQR THE NEUTRALI REMOVAL 0F THEIR PATTY ACID 2 Sheets-Sheet 1 Fle'd Match 5, 1923 Nov. 8, 1927. 1,648,367

J. w. sPENsLEY TREATMENT OF OILS AND FATS FOR THE NEUTRALIZATION AND REMOVAL OF THEIR FAI'TY ACID CONTENT Filed March 5. 1923 2 Sheets-Sheet 2 gwuemtoz akamu' .455 mill are broken up and Patented Novi s, 1921. y UNITED sTATEs PATENT OFFICE.

JAcoE WILLIAM srENsLEY, or MANCHESTER, ENLANn.

TREATMENT oF oILs AND EA'izs For. THE/NEUTE'ALIZATION AND 'nEMo'vAn 0E THEIR f I EATTY ACID 'coNTEN'n Application led March 5, 1923, Serial No.A

This invention relates tothe treatment of oils and fats for the neutralization and removal of the whole or any required proportion of their fatty acid content. The invenduction of edible oils and fats, but its use is not limited thereto. Oils as delivered from the Crushers always contain a percentage of fatty acids, and before they can be sold as 1ov edible oils and fats this fatty acid content must be eliminated. Hitherto the usualv order to complete the removal of the lfatty acids so much caustic alkali must be added that about as much of the neutral fat is saponiie'd as the amount of fatty acid present, and this represents a substantial loss of oil. It is therefore a desideratum to provide a process whereby only about so much alkali need be used as is required to saponify the free fatty acid, and whereby none or but very little of the neutral fat is saponiied or contaminated.` It is the principal object of the invention to attainthis result.

The desired result is attained according to the invention by bringing the oil andalkali into extremel intimate contact by passing them throug i a high speed centrifugal pinned disc milll and then separatlng out the saponified product formed. Very little if any excess of alkali need be used, and practically .none of the neutral fat is s aponified.

The preferred type of mill for intimately mixing theoiland alkali for theV purposes ofthe prsent invention is thatset forth in my Patent No. 1,515,798, dated November 18, 1924. In this mill the discharge from the g rotatin pinned disc is .free to take place substanti y' lall around the circumference 'of lthe mill, the discharged product being re- .ceived in a suitable surrounding vessel or hopper. The rotating disc can hel run up to a speed of about 20,000 feet per'minute at of the disc, and at such alkali paing through the intermixed so finely u the circumference speeds the oil and .fatty acid is almost instantaneous.

tion isparticularly applicable to the pro` the soap, s'o that a 623,069, and in Great Eritain may 5, 1922.

that the- -reaction between the alkali and the There is no risk of overheating although theV mechanical action is a violent one because the mill draws 1n a strong current of air which passes through with the oil andalkali mixture, and if the receiving chamber around the open discharge of the mill were left open at the top, the air around would be filled with a mist or spray'of finely divided particles. The 'receiving chamber is of course enclosed with suitable means for permitting of escape of air and separation of the oil spray therefrom. Instead of caustic soda for the saponify ing process- I can use soda ash (NaZCOa) or other forms of alkali, and this represents a substantial economy in raw materials.

The process is applicable to the removal o f fatty acids from animal oils such as whale oil, and from vegetable oils such as cotton seed oil, palm kernel oil, cocoanut oil,l soya bean oil and so forth. An incidental-advantage' of the process is that the oil is substan. tiallydeodorized in passing through the mill, this effect' being probably due to the fine fsubdivision effected coupled with the intimate mixture with the strong air current l which carries off' the volatile scented essences.

In addition to the use of theI process for producing edible oils and fats', it is applica ble also for raising the quality of oils by the partial neutralization and removal of;

attained according to the invention by adding to the oil rather less of the alkali, pref.l

erably soda ash, than that required for complete saponiication, before the treatment vin the pinned disc mill, and then separating out by any suitable method the soap stock formed by the treatment in the pinned disc mill. Separation may be effected by passing through a-sieve or a filter or bydecantation of the oil. The process'has the great advantage that the ash content of the crude whalel oil is largely removed in the saponification and subsequent separation.

One suitable form of apparatus for carryingl out the present invention is illustrated 2 is a half elevation of a mill with and Fig. the openV dischargering which I ,preferl touse in my in Fig. 1 of the-annexed drawing;

process disclosed herein and which is covered by my said Patent No. 1,515,798.

Referring to Figure. 2, a represents the shell or standard of 'the mill in which the driving gear is contained. At the top of this'shell is a plate y secured by screws c and Whose livery ring b. The rotating disc d of the mill is secured to the driven vertical shaft which is carried in ball bearings in a suitable lmanner in the plate y, as' indicated by way of example. The stationary top disc e is supported. by a number of lugs f,four 1n the example-shown, on the delivery ring b,

- and is secured by screws g engaging in these preciabl v pins. h is a feed hopper at of'fatty acid which it lugs. The bottom disc b which rotates has concentric rows of upwardly projecting pins upon it, while the top disc e which is station-V pins inary vhas similar concentric rows of Y tercalatingwith those on` the discd. Hither.- to,- in pinned disc mills, the lower disc which rotates, has always carried the outermost row of pins, this eing'essential in the case of mills with a tangential discharge in order to insure the throwing out vof the ground materials through such discharge. 'A fea` vture of my disintegrating mill is that-it enables meto apply an .additional annular row of pins z to the upper fixed. disc e, outside the last row of pins on the lower disc d, and so to improve the enciency of the mill. I

find that pins e, the material is ground toA a. greater degree of neness in one passage-t-hrough` the mill, without the consumption of apof choking the mill owing Vto the open circumferential discharge. .The current of air which the rotation of the lower disc induces-,5

throu' h the mill is quite suicient' to insure that the additional outermost row of stationary the centre of the top disc for delivering the materials to be treatedon to the surface of the rotatingy or practicall purposes therefore thewhole of the'dischar lreais directly.l open so that the materials thrown 'otfrom the circumference theievol 'without collectinganyw` inside o e mill.

As an'axample of. the removal of free fatty acid from .oils the following may be given: A certain whale oil contalns 10.3%l

is desired to remove circumference vconstitutes the dewith the 'addition' of. this row` of' more power,and' without any riskv e material isblown cleanly through oil to be treated are run simultaneously from the tank a to the inlet hoppers b, 'c of vtwo pinned disc mills d, e. The majority ofthe .free fatty acid in the whale oil is saponied fatty acid is reduced and the amount of free down to 0.5% the mills. The the casings f', the chutes h, lc intol the tank l and the saponified product separated vout-by any suitableV method as already mentioned. The oil may be run out throughthe pipes m, lr1.Sub- "stantially none of the neutral fat in the whale oil will have been attacked by soda ash in the treatment.

` The oil to be treated may be lpassed through the mill in la cold' condition or it may be preheated if desired, but it need not be heated in any case to a temperature nearly as high as `the boiling point of the oil, and the reaction can be completed without any heating of the oil.

Many variations in the practical details of the application of the process can be made without departing from the scope of the invention, and of course the oil and alkali may be passed more than once through the pinned on a single passage through products are discharged into g ofthe mills'and run downl discmills before theseparation of the Asoap stock. For this purpose, a circulating pump o is ,shown for raising the liquid from the tank 'Z so that it flows again into the tank a at p.

Having thus described my invention whatn I claim as new and desire to secure by L etters Patent isz- 1. The process o f preparing a neutral oil substantially free fromY fatty acid, which` consists' in Vtreating animal and vegetable oilscontaining free fatty acidand substantially only the amount of alkali required for' neutralization of the fatty acid thereof to combined high speed mechanical disintegration and centrifugal expulsive force, where- -byv the alkali combines with fthe free fatty Vacid content of the oil and simultaneously -saponies it, and then separating the sub stantially neutral oil from the soap stock formed.

2. The process for preparing a neutral oil substantially free from fatty, acid, whichconsists in treating animal and vegetableoils containing free' fatty acid, with a solu-- tion of soda ash substantially only suicient in amount for neutralization of the .fatty acid content thereof, subjectin the mixture to1 combined high speed mec anical disintegration and centrifugal expulsive-force, v

whereby the soda ash combines with said free fatty acid content of vthev oil and saponies f it, and then separating the substantially neutral oil from the soap stock formed.

3.` The process for preparing a neutral oil substantially free from fatty acid which consists in treating animal and vegetable oils containing free fatty acid, with a solution i of soda ash substantially only sufficient in4 tween agitatng and disintegrating mem- 10 bers having a relative peripheral'speed up to 20,000 feet per minute, whereby the soda ash combines with said free fatty acid content of the oil and saponies it, and 'then separating the remaining oil from the soap 15 stock formed.

JACOB WILLIAM sPENsLEY. 

